In the metal casting art, a continuous casting process is known in which a molten metal is ejected from a crucible through a nozzle onto a surface of a moving chill body, as described in U.S. Pat. No. 4,142,571 to Narasimhan.
The casting apparatus, which may be used for casting metal filaments, such as strips, sheets, ribbons or even round or square wire of amorphous metal alloys, includes either a moving chill belt or an annular chill roll as the moving chill body or substrate.
In the prior art, it is recognized that the moving chill substrate may be cooled on the surface opposite to the surface upon which the molten material is received. Thus, in U.S. Pat. No. 2,383,310 to Hazelett, for example, a melt is deposited on the outer surface of the main cooling ring 5, and pressurized water is discharged through a number of nozzles 38-1 against the inner surface of the ring for cooling the ring.
While Hazelett recognizes the need to avoid contact between the metal and cooling water, the only precaution taken is the provision of a chamfer in a roll in which the cooling ring travels, as well as the provision of a surfacing ring which is wider than the roll thereby to permit water runoff without contact with the molten metal. Such an approach, however, does not provide an efficient means for positive prevention of water coolant from reaching the outer surface of the ring. Thus, the detrimental effects of a contact between the coolant and the metal may be experienced in the Hazelett structure due to seepage of the coolant towards the outer ring surface.
U.S. Pat. No. 3,976,117 to Olsson shows, at FIG. 14 thereof, a sprayer for a coolant directed at the underside of a travelling belt used in a casting apparatus. The upper surface of the belt provides the chill surface for the solidifying molten metal. No provision is made, however, for assuring that none of the coolant seeps to the upper surface, where it may adversely affect the strand of metal being cast. The only disclosure of removal of a liquid from the belt is related to removal of a cleaning liquid, where a rubber squeegee 134 is used to remove the cleaning liquid from the same surface of the belt which receives the solidifying metal.
The prior art thus fails to provide adequate measures for assuring that moisture or other contaminants found in the coolant do not travel to and contact the chill surface of a moving substrate. Such failure may lead to contaminated, poor quality cast ribbon or filament.